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Updated: Aug 5, 2026
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Spontaneous Formation and Rearrangement of Artificial Lipid Nanotube Networks as a Bottom-Up Model for Endoplasmic Reticulum
Published on: January 22, 2019
Membrane lipid composition and rapid endocytic retrieval modulate Wingless secretion
Ines Alvarez-Rodrigo1, David Willnow2, Cyrille Alexandre2
1The Francis Crick Institute, London, UK. ines.alvarezrodrigo@crick.ac.uk.
The EMBO Journal
|August 3, 2026
Summary
Wingless secretion relies on Wntless cargo receptor and rapid endocytosis to prevent aggregation. Membrane lipid composition influences Wingless stability and release, ensuring proper basolateral secretion.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Wnt family ligands are crucial signaling molecules.
- These ligands possess a lipid moiety requiring protection from aqueous environments.
- Wntless acts as a cargo receptor facilitating Wnt secretion.
Purpose of the Study:
- To elucidate the mechanism of Wingless (Wnt) secretion.
- To investigate the role of endocytosis and lipid composition in Wnt trafficking.
- To understand how Wingless avoids aggregation during secretion.
Main Methods:
- Acute endocytosis inhibition experiments.
- Super-resolution microscopy.
- Analysis of Wingless aggregation and solubilization using lipid-binding proteins and liposomes.
Main Results:
- Wingless dissociates from Wntless at the apical membrane but is retained by endocytosis.
- Wingless traffics independently of Wntless through Rab7/Rab4-positive endosomes for basolateral release.
- Inhibition of endocytosis or ceramide synthase leads to apical release in punctate structures, suggesting aggregation.
Conclusions:
- Rapid endocytosis is essential for preventing Wingless aggregation and ensuring orderly secretion.
- Membrane lipid composition may regulate Wntless-Wingless complex stability and Wingless lipid accommodation.
- These processes collectively ensure efficient basolateral secretion of Wnt ligands.
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